Displacement machines with four parallel synchronous rotors

The paper presents two new rotational displacement machines designed for use in compressors, pumps and motors. In these machines, the displacement space is created between four parallel rotors rotating in the same direction at the same angular velocity. The paper presents the essence of the new machines and the test results of prototypes in the compressor version. The test results and conclusions corroborate the correctness of the construction concept of the new machines and allow one to indicate technological possibilities of their implementation, expose certain constructional shortcomings and describe possibilities for corrections. The results and conclusion also show the directions for future research to optimise the design of the machines.